From: Tom Cloyd <tomcloyd@...>
Date: 2009-07-16T10:11:05+09:00
Subject: problem executing bash script from ruby

I have little experience with this sort of thing, but it looked fairly 
straightforward. I'm in trouble, however.

Details:

 From /home/tomc/Ruby-work/setnet/bin/ I launch "./setnet". This dir 
contains:
mkrdoc.sh  setnet

"./setnet" contains these lines (among others), and works fine:

manager = SN::DBManager.new()
manager.startup

The "SN.rb" module is in "/home/tomc/Ruby-work/setnet/lib/setnet", and 
contains a method with this code snippet -

puts "\n=== generating new rdocs for SetNet ==="
system("ls")  # to verify where I am in the filesystem
system("./mkrdoc.sh")
if $? != 0
  puts "*** command failed: status = #{$?.exitstatus}"
end

This snippet executes by means of selection from a menu, with this result -

=== generating new rdocs for SetNet ===
mkrdoc.sh  setnet                     
*** command failed: status = 127 

mkrdoc.sh contains:

cd ../lib/setnet
echo "dir--"
ls
echo "rdoc executing --"
rdoc -N -x ./doc

What I'm trying to do is acquire the functionality of generating new 
rdocs for my program without having to manually go back to a command 
line. Every attempt I made to make a single "system()" call from within 
ruby, to generate the rdocs, have failed. In my experience, rdoc is 
excessively quirky. I've spent most of today trying to get it to do some 
simple things, and failing, even though I've very carefully following 
the documentation. I do have something that works - that "rdoc -N -s 
./doc" command, but only when it's executed from within the right dir.

Since -
* I'm allowed one command per "system()" call, and
* upon return from that call, the present working dir is reset to its 
prior state...

my only option appears to be to issue the commands I'd use in a manual 
interaction with the CLI from within a script file, and that's what I'm 
trying to do.

My questions:

1. Is there some obvious reason by my attempt to execute mkrdoc.sh is 
failing?
2. How can I make use of the process status output I've captured? I've 
searched Pickax 3rd ed., and with Google, and I'm not receiving much 
enlightenment. What do the "big boys/girls" do with this status output?

Thanks very much for any help anyone can offer.

Tom

-- 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Tom Cloyd, MS MA, LMHC - Private practice Psychotherapist
Bellingham, Washington, U.S.A: (360) 920-1226
<< tc@tomcloyd.com >> (email)
<< TomCloyd.com >> (website) 
<< sleightmind.wordpress.com >> (mental health weblog)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~